Field of the Invention
The present invention relates generally to an apparatus for separating heavy particles (10.0 and heavier specific gravity) of ore and other critical and strategic rare earths and precious metals.
Background of the Invention
In the early eighteenth century period, gold particles are discovered in sand and gravel of stream and riverbeds resulting in the development of different types of apparatus for the separation of gold particles from the sand and gravel. These apparatus employed different separation mechanisms such as using water to wash away the sand, gravel and other particles, retaining only the gold and other heavy metal particles. The above method works on the basis of the difference in specific gravity of gold and other heavy metal particles with sand, gravel and other light dirt particles. The heavy gold and other heavy metal particles having specific gravity of ten and more moves to the bottom of the apparatus during the washing process, which can later be retrieved for further processing. One such apparatus to exploit the difference in specific gravity is provided with a gold pan having a frustum, or truncated conical cylinder, with mildly inclining sides closed on its smaller end by a flat bottom. The method of separation of the heavy gold and other metal particles includes the steps of pouring an amount of raw mineral matter, which contains both light and heavy particles, in the pan and adding appropriate amounts of water. Then the raw mineral matter with the water in the pan is agitated to separate comparatively large pebbles from the finer mineral matter. The agitation action raises large matter above the fine matter. The pan is then moved in a circular motion with the pan sidewall inclined slightly below horizontal to wash away light sand material. With the water moving on the pan sidewall without excess spillage, a swirling action washes the mineral matter with the large and lighter matter being washed off of the pan. In further washing of the matter with gentle agitation, small particles are lifted into the water to create a temporary suspension of the particles with particles of high specific gravity quickly falling back down to the pan sidewall while low specific gravity particles remain in suspension. Thus, particles are separated by specific gravity as particles of low specific gravity are suspended, carried and washed away in water. The process does not achieve a well-defined single separation but a continuum of separation, so it is necessary to repeat the process, progressively separating heavier particles from lighter particles until only the very heaviest, such as gold and other metal particles, remains.
However, even the most skilled gold panner is not successful in recovering all of the gold mixed in the mineral matter using the traditional gold pan. Washing away low specific gravity particles also tends to wash away very small particles of high specific gravity with the sand. To improve the efficiency of the pan, various improvements have been attempted. One such improvement includes employing steps on the pan sidewall that create a pocket to capture the high specific gravity particles falling quickly out of suspension as the suspension flows as a layer over the steps. With the pan sidewall leaning slightly downwardly from horizontal, water progressively falls over succeeding steps and out of the pan carrying low specific gravity particles in suspension with it, as heavier particles fall out of suspension into the corners of the steps. However, all such methods are proved to be unsuccessful and time consuming to recover all or most of the gold and other heavy metal particles from the raw mineral matter.
Another improved apparatus for separating the heavy particles employs a spiral guide wall on the pan sidewall instead of concentric steps. As the pan is rotated instead of moved in a customary circular or orbital motion, small, high specific gravity particles are urged inwardly into the pan center along the guide as low specific gravity particles are washed in suspension from one spiral step to another until they fall out of the pan. However, this method is also proved to be unsuccessful in recovering all or most of the gold and other heavy metal particles from the raw mineral matter.
However, with the introduction of electric motors, the process of separating the gold and other heavy metal particles from the raw mineral matter is performed automatically by rotating the pan having the spiral guide and carrying the mineral matter at a specific angle. The spiral guides traps the gold and other heavy metal particles and guides it through the grooves of the spiral guides to the collecting point. However, many apparatus employing the above said method is not proved to be successful in recovering all or most of the gold and other heavy metal particles from the raw mineral matter. Accordingly, various prior arts have disclosed such related inventions, whereby the provided following patents are herein incorporated by reference for their supportive teachings and enablement criteria for the technology needed to enable one skilled in the art to make and use the subject invention, in which:
U.S. Pat. No. 4,561,973 A titled “Ore concentrator pad assembly” and issued to Cleland Keith discloses a concentrator pad assembly for the concentration of ores. The ore-concentrating apparatus comprises a frame or support, the upper portion of which is pivotable about a horizontal axis in order to adjust the inclination of a drive shaft. Such shaft, when driven by a motor assembly, effects rotation of a fiberglass shell about an axis coincident with that of the shaft, the shell is connected to the shaft by a spider assembly. A hydraulic system effects pivotal movement of shaft and the shell about axis. The motor assembly drives the shaft and shell clockwise and the ore is simultaneously conveyed into the drum by a conveyor. At the same time, lubrication water is sprayed toward the concentrator-pad by spray apparatus. Because of complex gravitational, frictional, and wave actions, the more dense components of the ore are caused to move toward the center of the concentrator-pad assembly and flow outwardly through a central opening for collection by a suitable receiver. However, this apparatus and method of separation is also proved to be unsuccessful in recovering all or most of the gold and other heavy metal particles resulting in the loss of some of the heavy particles with the water.
U.S. Pat. No. 4,522,711 A titled “Ore separator apparatus” and issued to Cleland Keith discloses a rotary bowl for separating particles of ore received in the bowl. The rotary bowl is engaged to a drive rotor. The rotor is made tiltable with the bowl. An idler rotor may be provided to engage the back outer surface, and to cooperate with the drive rotor to provide bowl support. However the tilting and rotating of the bowl still proved to be ineffective in capturing all the gold particles in the grooves.
U.S. Pat. No. 4,406,783 A titled “Apparatus for separating ore” and issued to Cleland Keith discloses an ore separating device of the rotating wheel type, which includes a container, which may be of fiberglass, having a concave portion and an annular flange at its periphery with a pad having ridges on its outer surface complementarily overlying the concave portion and removably secured by fasteners. An annular rim complementarily overlies the peripheral portion of the container and is removably held therein by forwardly inclined vanes, which agitate the ore during rotation of the container. However the curvature, the tilted position and the rotation of the rotating wheel is proved to be ineffective in capturing all the gold particles in the spiraling grooves.
Another prior art U.S. Pat. No. 4,517,079 A titled “Ore separation system” and issued to Cleland Keith discloses an apparatus having a number of ore separating rotary bowls, which are combined in staggered, closely spaced relation to facilitate efficient use and transportation. However the curvature, the tilted position and the rotation of the rotating wheels or the bowls is employs above said steps and addition of multiple bowls is not proved to be effective in capturing all the gold particles in the spiraling grooves.
U.S. Pat. No. 5,447,239 A titled “Gold pan with flukes and stratifiers” and issued to Tubbs, Jr. and George discloses a traditional gold pan with a flat center base with a spiral sidewall guide from a vertical pan rim to the pan base. The spiral sidewall guide incorporates a number of obtuse flukes on the spiral extending into the spiral path to disrupt smooth flow of water and mineral matter. A spiraling guide is also provided on the base leading to a cup at the pan center. On the spiraling base guide is a number of stratifiers extending from the guide base into an outer spiral path. The pan is continuously rotated by an electric motor linked to the back of the by a belt and pulley. However, this apparatus and method of separation is also proved to be unsuccessful in recovering all or most of the gold and other heavy metal particles from the raw mineral matter. (Not for commercial mining production)
In all the above prior arts, especially the patents, U.S. Pat. Nos. 4,522,711 4,406,783 A, 4,561,973 A, discloses a concave shaped bowl or wheel design, but the concave wheel does not have a negative draft riffle to trap and enable the upward movement and separation of the heavy particles. The above patents disclose squared riffles (90 deg. from base) relying on the tilt of the apparatus to capture the heavy materials. With no negative draft, the water knocks off the concentrates instead of transporting to the center drop through of the wheel, especially on flat backs. In some of the prior arts, the concentrating wheel can be tilted to hold the heavy materials only for a split second until the water flushes the heavy material out of the riffle, as there is no negative draft to hold the material in to collect and move up the concentrating wheel.
Despite the various teachings of the incorporated references provided above, none of the art taken singly or in combination provides an effective apparatus and a method for effective or optimal separation of the gold and other heavy particles from a mixture of light and heavy particles. Hence, there is a need for an improved apparatus that would be capable of separating the heavy particles and effectively guiding the heavy particles through spiraling grooves to a collection point. Moreover the needed apparatus would have a number of teeth uniquely shaped so that they form a negative draft. Up to this time, there has not been a single apparatus offering teeth with negative draft for the effective separation of the heavy particles including gold from the mixture of light and heavy particles.